US Startups Heat Up The Solid State EV Battery Race

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US President Donald Trump has been attacking the domestic EV industry from all angles, the latest move being a pledge to roll back CAFE (Corporate Average Fuel Economy) standards set during the Biden administration. You do you, Donald. In the meantime, though, the global EV industry is marching forward with a healthy assist from US innovators in the solid-state EV battery field.

CAFE Or Not, Here Comes The Solid-State EV Battery Of The Future …

This year’s sharp U-turn in federal energy policy has already thrown EV sales momentum for a loop. With the support of President Trump, in the summer the Republican-controlled Congress rescinded a $7,500 federal EV tax credit, leading to a sharp plunge in EV sales in the US after the credit ended on September 30. In contrast, EV sales continue to rise in Europe and other markets where public policy is not as vulnerable to partisan politics.

The long term outlook for the US market looks somewhat less gloomy. The cost of EV batteries has been dropping and US automakers expect to produce more affordable EVs in the coming years, with an assist from new LFP batteries. However, over the near term, auto industry insiders anticipate that the CAFE rollback will further depress EV sales, by reducing the upfront cost of buying gas-fueled vehicles.

Into this picture jumps solid-state EV batteries. As the name indicates, solid-state EV batteries do not have the liquid electrolyte found in conventional lithium-ion batteries. Instead, they deploy an electrolyte made of high-tech ceramics or some other solid material.

Small-scale solid-state batteries are nothing new, but scaling up the technology for use in EVs has posed a formidable R&D challenge. Nevertheless, auto industry stakeholders have invested much time and effort into the idea, attracted by the potential for cutting costs while improving range, reducing charging times, and eliminating the toxicity and fire hazards that characterize conventional Li-ion batteries. Solid-state batteries are also lighter and more energy dense than their Li-ion counterparts, providing automotive engineers and stylists with a greater range of design flexibility (see more solid-state background here).

… Eventually!

Among the solid state innovators attracting attention from the auto industry is the Massachusetts-based startup Factorial Energy. The company’s “FEST” semi-solid-state EV battery has been crisscrossing the CleanTechnica radar since 2021, when Mercedes-Benz (formerly Daimler) and Stellantis expressed interest in the new technology (see more Factorial background here).

In 2024, Stellantis followed up with plans to field a fleet of FEST-equipped Dodge Charger EVs in 2026. Though, the timeline has reportedly been pushed to 2027 according to Motor Trend.

As of earlier this year, Stellantis was still committed to making its investment in FEST EV batteries pay off sooner rather than later. In the meantime, Factorial has been moving the R&D needle on its plans for developing a full, 100% solid-state EV battery under the name “Solstice.”

In the latest development, Factorial and the POSCO Future M branch of the Korean conglomerate POSCO Group have hooked up in a non-binding Memorandum of Understanding to collaborate on solid-state EV battery technology.

EVs are actually just part of the plan. “Under the MOU, the two companies plan to explore cooperation in developing materials for all-solid-state batteries, which are powering progress in next-generation industries such as electric vehicles, robotics, energy storage systems and more,” the two firms explain.

“We expect synergy in the next-generation all-solid-state battery business based on Factorial’s battery technology and market presence with global automakers, and POSCO Future M’s competitiveness in cathode and anode materials,” elaborated POSCO Head of Research Hong Young-Jun.

US Innovators Keep Pushing That EV Envelope

Factorial anticipates that the collaboration with POSCO will support a reliable, global supply chain for its solid-state EV batteries, complementing its South Korean factory as well as a facility in its home state of Massachusetts.

Factorial is just one example. Another US contender in the solid-state field is the Colorado startup Solid Power, which recently leveled up its ongoing relationship with BMW.

Earlier this year, BMW let word slip that its interest in Solid Power was on the cusp of payoff, and in October the automaker was ready for a more definitive statement. “Under the newest stage of collaboration with BMW, Solid Power will contribute its sulfide-based solid electrolyte to Samsung SDI for use in fabricating solid-state battery cells,” CleanTechnica reported on October 30.

Another player is the California startup Quantumscape. It was no surprise to see Volkswagen’s PowerCo branch taking Quantumscape’s new solid-state battery out for a spin last year, considering that Volkswagen is a Quantumscape investor. More recently, this year, Quantumscape joined forces with the legacy firm Corning in a new battery manufacturing venture. The two firms also partnered in a showcase of solid-state technology, featuring a Ducati motorcycle.

The Global EV Battery Race Heats Up, With Or Without The US

Although competition abounds in China and elsewhere, US innovators like Factorial, Solid Power, and Quantumscape have a good shot at leading the auto industry into the solid-state EV battery of the future — if not here in the US, then in other markets around the world.

And there is still plenty of innovating left to go around. Earlier this year, for example, researchers at Argonne National Laboratory recapped their efforts to improve solid-state batteries with lithium-metal electrodes.

“Because all atoms in lithium metal can participate in the charge and discharge of a battery — enabling it to store more energy — lithium metal has a higher energy density than graphite, a conventional electrode material,” the lab observed.

The lab points out that LLZO (lithium lanthanum zirconium garnet) solid electrolytes are excellent candidates for lithium metal electrodes. The next-level challenge is to identify other additives, such as gallium or aluminum, that improve electrolyte performance without degrading the electrodes.

Considering the topsy-turvy state of federal policy at the moment, all that hard work is unlikely to pay off — at least not here in the US. Automakers in Europe, though, could benefit. The research was conducted under the Vehicle Technologies Office of the US Department of Energy, through the US-German Cooperation on Energy Storage program. The University of California–Santa Barbara provided the LLZO material for analysis at the Heinz Maier-Leibnitz Zentrum in Germany and the Nuclear Physics Institute of the Czech Academy of Sciences in the Czech Republic.

Photo: US innovators are continuing to support the global movement towards solid state EV batteries, with the Massachusetts startup Factorial Energy among the contenders (cropped), courtesy of Factorial.